DE 39 16 840 C2 discloses a dimensionally stable plastic ampoule for a liquid (fluid) which can be withdrawn from the ampoule by a syringe body. The syringe body, on its end to be inserted into the ampoule neck, has a withdrawal nozzle in the form of a cone. The inside wall of the ampoule neck in the area intended for contact with the cone is provided with a sealing zone preventing passage of liquid between the cone wall and the inside wall of the ampoule neck and yielding contact along a circular line. In that in the known solution, the free end of the neck of the ampoule is configured as a contact surface for the face of the syringe body bearing the cone. In the longitudinal direction of the neck, the free end has a distance from the sealing zone. When the face of the syringe body abuts the contact surface of the neck, the contact pressure of the cone against the inside wall of the neck is limited to a value which ensures entry of air between the wall of the cone and the inside wall of the neck while maintaining an obstruction for passage of liquid. When the syringe is drawn up normally by the syringe plunger, liquid can be easily withdrawn manually, even if the ampoule, as is customary, is standing on its head for the withdrawal process, that is, with its neck part is pointing down.
In practical applications, a very rapid drawing-up process by the syringe can cause a type of short. The liquid remains in the container part of the ampoule. Essentially, only air is subsequently suctioned into the syringe body in the withdrawal process. That air is stored at least also in part in the container part of the ampoule if the ampoule is not completely filled with the pharmaceutical liquid.
Attempts have been made to achieve increased air entry from the outside to the inside by the inside wall of the ampoule neck in the area intended for contact of the cone of the syringe body forming an annular bead. The annular bead projects radially to the inside from the adjacent inside wall areas. A section of the neck part intended for contact with the cone on its inside is provided with at least one longitudinal or axial groove. The groove is open to the inside and extends parallel to the longitudinal axis of the ampoule to raise the entry point for ambient air in this way. Such attempts are not proven sufficient to effectively solve the problem of a ventilation short in rapid withdrawal processes.
U.S. Pat. No. 5,716,346 discloses a process for filling a syringe or cannula with injectable fluids from a storage ampoule. The syringe is equipped with a first coupling element and an opening connected to the inner cylindrical cavity of the syringe (Luer lock system). The liquid flows past the first coupling element and through the opening into the cylindrical cavity and fills the syringe or cannula. In this way, a connection is established which is sealed liquid-tight. Accordingly, the ampoule can be provided with elastic walls which collapse under the negative pressure in the withdrawal process by the syringe or cannula body, and thus, ensure the withdrawal process. The pertinent withdrawal process which is to take place airtight with the known device consequently cannot be applied to dimensionally stable ampoules in this way. As a result of the “collapsible ampoule walls”, a negative pressure forms within the ampoule with the result that in the withdrawal process by the syringe the contents are necessarily suctioned back again into the ampoule.